Hi, guys, could you, please, give me a hand with one phrase...
There are two thermostats...
*one of which is a control-type one and the other one is the safety one.
*one of which is of a control type and the other one is safety.

Which ending is better? Yeah, I do understand, that may be there are way too many "ones" in the first (one??, or not required, btw:)), but can we really use the ajective "safety" before the full stop without any word like "one" here? Please, could you explain this to me.

Hi, guys, could you, please, give me a hand with one phrase...
There are two thermostats...
*one of which is a control-type one and the other one is the safety one.
*one of which is of a control type and the other one is safety.

Which ending is better? Yeah, I do understand, that may be there are way too many "ones" in the first (one??, or not required, btw:)), but can we really use the ajective "safety" before the full stop without any word like "one" here? Please, could you explain this to me.

I would say "one of which is a control type, and the other which is a safety one"